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Theoretical modeling of electron mobility in superfluid (4)He
Frédéric Aitken1, Nelly Bonifaci1, Klaus von Haeften2
1G2ELab-GreEn-ER, Equipe MDE, 21 Avenue des Martyrs, CS 90624, 38031 Grenoble Cedex 1, France.
The Journal of Chemical Physics
|August 1, 2016
Summary
This study extends the Orsay-Trento model to include superfluid helium-4 dissipation. The model explains ion mobility data, revealing insights into bubble sizes in liquid helium.
Area of Science:
- Condensed Matter Physics
- Quantum Fluids
- Superfluidity
Background:
- Superfluid helium-4 exhibits complex dynamics at finite temperatures.
- Understanding dissipation is crucial for modeling superfluid behavior.
- Previous models did not fully account for viscous effects at interfaces.
Purpose of the Study:
- To extend the Orsay-Trento bosonic density functional theory model.
- To incorporate dissipation from viscous response in superfluid helium-4.
- To investigate ion mobility and bubble sizes in liquid helium.
Main Methods:
- Extended the Orsay-Trento model with a viscous functional derived from Navier-Stokes equations.
- Incorporated interfacial viscous response at gas-liquid boundaries.
- Calibrated the model against experimental electron mobilities (1.2 K–2.1 K) dominated by thermal rotons.
Main Results:
- Calculated temperature-dependent ion mobility for various solvation cavity sizes.
- Rationalized results using roton scattering and Stokes limited mobility models.
- Provided estimates for bubble sizes by comparing with experimental "exotic ion" data.
Conclusions:
- The extended model successfully incorporates viscous dissipation in superfluid helium-4.
- The study offers insights into the nature of "exotic ions" and their associated bubble sizes.
- The findings contribute to a better understanding of ion transport in quantum fluids.
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